.clearfix {
    display: block;
    clear: both;
    float: none;
}

body {
    display: block;
    margin: 0;
    padding: 0;
    font-family: 'Roboto', sans-serif;
}

.video-back {
    display: block;
    padding: 200px 0px 0px 0px;
    text-align: center;
}

.video-back h1 {
    display: block;
    text-align: center;
    color: #fff;
    font-size: 50px;
}

.video-back p {
    display: block;
    color: #fff;
    margin: 0px;
    padding: 0px;
    margin-bottom: 20px;
}

.video-back img {
    width: 150px;
}

.jq22-demo a {
    color: aliceblue;
    font-family: "微软雅黑";
    font-size: 20px;
    text-decoration: none;
    padding-left: 10px;
    padding-right: 10px;
    font-weight: bold;
    text-shadow: 2px 2px 4px #000;
}